Reference Yeast and Human Whole Cell Protein Extracts for Mass Spectrometry Instrument Performance Monitoring and Method Development

  The mass spectrometry-compatible yeast and human protein extracts are designed specifically for mass spectrometry applications.   The extracts are predigested and cleaned up by solid-phase extraction for immediate use in liquid chromatography/mass spectrometry (LC/MS) analysis. Both the yeast and human extracts also are available in an intact undigested form to provide a test material for optimizing mass spec protein sample preparation. The yeast extracts are beneficial for users who prefer working with a relatively compact and well studied proteome, whereas the human extract provides opportunity for working with a complex proteome having a large dynamic range. Consistent extract protein composition is ensured by tight control over cell culture conditions and manufacturing process. Lot-to-lot consistency of extracts is monitored by various protein and peptide qualitative and quantitation methods, including LC/MS and amino acid analysis (Table 1). Our manufacturing process assures compatibility with reverse phase liquid chromatography and mass spectrometry by monitoring nonspecific protein fragmentation, nonbiological post-translational modifications and, for digested extracts, minimal undigested peptides. Features & Benefits: Compatible with LC/MS instrumentation platforms. Minimal nonbiological post-translational modifications. Peptide quantity measured by AAA. Model systems for method development/instrument monitoring. Multiple formats (digest/intact).

Trypsin/Lys-C Mix, Mass Spec Grade, is a mixture of Trypsin Gold, Mass Spectrometry Grade, and rLys-C, Mass Spec Grade. The Trypsin/Lys-C Mix is designed to improve digestion of proteins or protein mixtures in solution.   Using the conventional trypsin digestion protocol (i.e., overnight incubation at nondenaturing conditions), Trypsin/Lys-C Mix improves protein digestion by eliminating the majority of missed cleavages, which occur at prominent quantities in trypsin digests. Trypsin/Lys-C Mix enhances digestion and compensates for the trypsin proteolytic inefficiency at lysine sites.     Trypsin/Lys-C Mix, Mass Spec Grade Features & Benefits: Simple to Use - Use standard overnight digestion with nondenaturing conditions. Enhanced Proteolysis - Increase peptide recovery, resulting in enhanced protein quantitation and improved reproducibility and eliminating the majority of missed cleavages (Figures 1 and 2). Tolerant to Trypsin-Inhibiting Contaminants - Generate mass spectrometry data from poor-quality sample material.